/* 重置样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* 基础样式 */
body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8fafc;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航栏 */
.navbar {
    background: #fff;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo h2 {
    color: #2563eb;
    font-weight: 700;
    font-size: 1.5rem;
}

.nav-search {
    display: flex;
    gap: 10px;
}

.nav-search input {
    padding: 10px 15px;
    border: 1px solid #e2e8f0;
    border-radius: 8px;
    width: 300px;
    font-size: 14px;
    transition: all 0.3s ease;
}

.nav-search input:focus {
    outline: none;
    border-color: #2563eb;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.nav-search button {
    padding: 10px 20px;
    background: #2563eb;
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 500;
    transition: all 0.3s ease;
}

.nav-search button:hover {
    background: #1d4ed8;
    transform: translateY(-1px);
}

/* 英雄区域 */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 80px 0;
    text-align: center;
}

.hero-container h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 20px;
}

.hero-container p {
    font-size: 1.2rem;
    opacity: 0.9;
    margin-bottom: 40px;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 60px;
    margin-top: 40px;
}

.stat {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 5px;
}

.stat-label {
    font-size: 1rem;
    opacity: 0.8;
}

/* 分类区域 */
.categories {
    background: white;
    padding: 40px 0;
    border-bottom: 1px solid #e2e8f0;
}

.categories h2 {
    text-align: center;
    margin-bottom: 30px;
    font-size: 2rem;
    color: #1e293b;
}

.category-tabs {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 10px;
}

.category-tab {
    padding: 12px 24px;
    background: #f1f5f9;
    border: none;
    border-radius: 25px;
    cursor: pointer;
    font-weight: 500;
    transition: all 0.3s ease;
    color: #64748b;
}

.category-tab:hover {
    background: #e2e8f0;
    transform: translateY(-2px);
}

.category-tab.active {
    background: #2563eb;
    color: white;
}

/* AI工具网格 */
.tools-grid {
    padding: 60px 0;
}

.tools-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
    margin-top: 30px;
}

.tool-card {
    background: white;
    border-radius: 12px;
    padding: 25px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    transition: all 0.3s ease;
    border: 1px solid #f1f5f9;
}

.tool-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 25px rgba(0, 0, 0, 0.1);
    border-color: #2563eb;
}

.tool-icon {
    font-size: 2rem;
    margin-bottom: 15px;
}

.tool-card h3 {
    font-size: 1.3rem;
    margin-bottom: 10px;
    color: #1e293b;
}

.tool-description {
    color: #64748b;
    margin-bottom: 15px;
    line-height: 1.5;
}

.tool-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 20px;
}

.tool-tag {
    background: #f1f5f9;
    padding: 4px 12px;
    border-radius: 15px;
    font-size: 0.8rem;
    color: #475569;
}

.tool-link {
    display: inline-block;
    padding: 10px 20px;
    background: #2563eb;
    color: white;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 500;
    transition: all 0.3s ease;
    text-align: center;
    width: 100%;
}

.tool-link:hover {
    background: #1d4ed8;
    transform: translateY(-1px);
}

/* 页脚 */
.footer {
    background: #1e293b;
    color: white;
    padding: 60px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h3,
.footer-section h4 {
    margin-bottom: 20px;
    color: #f8fafc;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 10px;
}

.footer-section ul li a {
    color: #cbd5e1;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section ul li a:hover {
    color: #60a5fa;
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #374151;
    color: #9ca3af;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-container {
        flex-direction: column;
        height: auto;
        padding: 15px 20px;
        gap: 15px;
    }
    
    .nav-search input {
        width: 200px;
    }
    
    .hero-container h1 {
        font-size: 2rem;
    }
    
    .hero-stats {
        flex-direction: column;
        gap: 30px;
    }
    
    .category-tabs {
        justify-content: flex-start;
        overflow-x: auto;
        padding-bottom: 10px;
    }
    
    .tools-container {
        grid-template-columns: 1fr;
    }
    
    .container {
        padding: 0 15px;
    }
}

/* 加载动画 */
.loading {
    text-align: center;
    padding: 40px;
    color: #64748b;
}

/* 空状态 */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: #64748b;
}

.empty-state h3 {
    margin-bottom: 10px;
    color: #475569;
}